This project has focused on the allergic inflammatory response seen in tissues after allergen exposure. In the first part of the project, the identification of the cells found in the human nasal mucosa were carefully measured, and then the effects of allergen exposure were examined. The resident cells consisted of lymphocytes, mast cells, and plasma cells. After allergen exposure, the major changes were activation of the lymphocyte (increased expression of the IL-2 receptor), an increase in eosinophil infiltration, and degranulation of mast cells. The bulk of the time on this project this year was spent developing techniques to measure cytokine expression quantitatively, to assess lymphocyte (increased expression of the IL-2 receptor), an increase in eosinophil infiltration, and degranulation of mast cells. The bulk of the time on this project this year was spent developing techniques to measure cytokine expression quantitatively, to assess lymphocyte phenotypes by FACS analysis, and to clone the human H-1 receptor.